Apparatus for forming pulp articles



- Au .30, 1938. E. ,HUFF ET AL APPARATUS FOR FORMING PULP ARTICLES Filed Dec. 2, 1935 3 Sheets-Sheet l INVENTORS W1 ATTORNEY$ Aug. 30, 1938. E. HUFF ET AL .APPAR1 \TUS FOR FORMING PULPARTICLES Filed Dec. 2 1935 3 Sheets-Sheet 2 INVENTORS 60:44)! 7 I BY MM *q ATTORNEYS Aug. 30, 1938. E. HUFF ET AL APPARATUS FOR FORMING PULP ARTICLES Filed Dec. 2, 1935 3 Sheets-Sheet 3 Patented Aug. 30, 1938 UNITED STATES 2,128,745 APPARATUS FOR FORMING PULP ARTICLES Ernest Huff, Rockford, Ill., and Andrew Keiding, Milwaukee, Wis., assignors to American Lace Paper Company, Milwaukee; Wis., a corporation of Wisconsin Application December 2, 1935, Serial No. 52,484

19 Claims.

This invention relates to improvements in apparatus for forming pulp articles. The present application .is a companion to the patent of Ernest Huff and Andrew Keiding, No, 2,023,200,

issued December 3, 1935, for improvements in the Art of molding pulp containers.

The present applicationv pertains to apparatus constituting one means for the practise of the process therein disclosed.

It is the object of the invention to provide novel and improved pulp molding apparatus capable of operating upon pulp blanks for the manufacture of containers of practically any desired form.

More specifically, it is my obdect to provide improved means for handling the wet pulp blanks during, before and after, the forming operation; to provide improved means for holding the blanks to a predetermined size and form; 20 to compress the blanks while protecting the pulp against unduly localized pressure such as would destroy the fibers and the felting thereof; and to substantially eliminate rubbing such as would 25 likewise destroy or reduce the waterproof or other desirable characteristics of a container made in accordance with the disclosure of the companion process application above identified.

In the drawings:

Figure 1 is a side elevation of the operative portions of mechanism embodying the invention as they appear when exposed by the removal of a portion of the frame and actuating connections.

35 Figure 2 is a view in elevation showing the opposite sides of the mechanism illustrated in Figure 3 is an end elevation of the mechanism.

shown in Figs. 1 and 2.

40 Figure 4 is a detail view in section on an enlarged scale showing the portion of the cam mechanism by which the mandrel shafts are tilted.

Figures 5, 6, 7, and 8 are detail views on an 45 enlarged scale illustrating partially in section and partially in front elevation the successive.

positionsof the mandrel, the forming die, and the work. I

Figure 9 is a view similar to Fig. 'l showing a 59 modified embodiment of the invention.

Figures 10, 11, and 12 are detail views showing in elevation the several'cains used to control the function of the parts.

Figure 13 is a fragmentary detail view in plan 55 showing the drive for the mandrels.

a transfer carriage by means of the cam 36 and rocker arms 31 and Like parts are identified by the same reference characters throughout the several views.

The machine includes any appropriate framesuch as that indicated at I4 through which extends the upper flights of conveyor chains IS.

The wet pulp blanks I6 containing preferably fifty to fifty-five percent of free water, are transported by trays I! from the molding apparatus to the conveyor l5. In the device as illustrated, each tray carries 2O blanks. The conveyor is actuated to advance the trays with a step by step movement, and in each dwell a tray is registered within the frame I4 beneath the mandrel carriage l8 which is rotatably mounted in the frame.

The mandrel carriage I8 is polygonal in form, and from each of its faces projects a series of mandrels l9 corresponding 1n number to the blanks of each tray.

The individual mandrels l9 have vents 2| opening to their peripheries as indicated in Fig. 5. These vents are inadequate in size or number to withdraw any appreciable amount of water from the pulp during the forming operation, it being our intention to compress the pulp without permitting the extraction of water therefrom to any great degree. The vacuum, however, holds the pulp to the mandrel, thereby preventing it from shifting thereon or increasing the size with respect thereto during the forming operation. The individual mandrels may preferably also be heated as indicated by the resistance coils 22 (Fig. 5). The coils may be supplied with current by means of slip rings'23 and 24 on the hub of each mandrel and. brushes 25 and 26 coacting therewith during the rotation of the mandrel on the stud 21 projecting from the face of carriage l8. The brushes in turn are carried with similar slip rings at 28 and 29 on the end of carriage I8 supplied with current from anysuitable source through the brushes 30 and 3|.

The vacuum and pressure alternately applied through the ducts 2! are provided for by the pipe-like bearings 21 which place the'interior of each mandrel in communication with the interior of carriage I8 and the stufiing box 32 (Fig. 3) with which the supply line 33 connects. The application and control of pressure and vacuum through rotary parts is well known, and'since the.

details are not important to the present invention they will need no further description.

At each dwell of the conveyor chains, IS the 35 will be Sharply lifted twice 38. In its first upward movement the transfer carriage will encounter the wet pulp blanks l6 to free them from their tray l1 and to lift them, and ultimately the tray, toward the rotary mandrel carriage l8. At this point the mandrels are subject to vacuum and the wet blanks in registry therewithwill adhereto the mandrels. The tray and'transfer carriage 35 will then be lowered and the mandrel carriage l8'will be rotatively indexed ninety degrees to bring a group of 1formed articles 46 into registry with the empty ray.

The elevator 35 is now raised for the second time to lift the tray to a position where it can receive the completed articles 40 from the mandrels. The interiors of. the several mandrels which are downwardly presented at this time are temporarily subjected to pressure instead of vacuum to effect the discharge of the articles 40 therefrom on to the tray. The next advance of the conveyor chains l5 moves the tray full of completed articles out of the frame and substitutes therefor another tray of wet blanks. While the articles 40 are referred to as complete, it will be understood that they have still to be dried, since practically no water is normally squeezed therefrom during the operations herein referred to.

The initial upward movement of the elevator 35 is effected by the broader lobe of cam 36 to give a dwell of sufiicient duration for the vacuum to become effective to hold the blanks to the mandrels. The second lift of the elevator is effected by the shorter lobe of cam 36 because no particular time is required for the discharge of the formed articles into the tray. In both upward movements of the elevator the elevator may convem'ently be counterbalanced as shown.

Only the articles on the mandrels at the top of carriage I8 in any given position of rotative adjustment thereof are worked upon. The mechanism for forming the articles is as follows.

There is a sub-frame verticallyslidable upon the rails 46 and including horizontal cross heads at 41 and 48. Extending therebetween are the spindle shafts 49. At its lower end each of the spindles 49 carries a die 50. These dies correspond generally in number and position to the mandrels I9, but in addition to the relative vertical or axial movement between the several dies and several mandrels provided for by slide 45, there is also a swinging or pendular movement of the spindles 49 which is utilized in the adjustment of the dies 50 in a lateral direction with respect to the several mandrels.

Fig. 4 shows the lower cross head 41 upon which the bearing blocks 5| of the several spindles 49 are laterally adjustable in suitable guideways. The outer side faces of the blocks 5| are beveled,

and the push rods 53 which are transversely re- The timing of the movement of the parts isindicated in Figs. 5, 6, '7, and 8. Each die 50 is laterally displaced in the course of its downward movement on to the work, so that it engages the work with a simultaneous rolling and drawing of the die is slightly greater than that of the side wall of the exterior periphery of the mandrel, so that the surfaces engaged in the compression of the pulp at one side of the mandrel will be approximately parallel in a vertical direction when the die is laterally displaced as shown in Fig. 6.

As explained in the companion application aforesaid, the slight drawing action produced by the relative movement illustrated in Fig. 5 displaces a certain amount of material toward the larger end of the pulp blank which is there available for filling the grooves of the die to create the embossed efiectillustrated. Since heat is desirable in the completion of the article the dies, as well as the mandrels, may preferably be equipped with electrical resistance coils at 62, or with some other suitable heating devices. The apparatus may be successfully employed, however, without heat, if desired.

By the compression without localized pressure as shown in Fig. 6 under the thrust of the cams 54 which laterally displace the bearing blocks 5| and the dies 50, we complete the forming of the article 40 from the blank l6. Thereupon the cams 6| effect the release of the camming elements 54 and bearing blocks 5| to allow the pendular movement of the spindles 49 to restore by gravity the dies 50 to their normal position of axial registration with the mandrels. are now entirely clear of the completed articles 40 and the return reciprocation of the slide 45 lifts each die clear of the article upon which it is operated, thereby leaving the carriage l8 free for a further indexing movement.

The construction shown in Fig. 9 is merely illustrative of the fact that devices of special formv may be made on this apparatus. So far as is known, it has not heretofore been possible to form an article having cylindrical walls. The article 400 illustrated in Fig. 9 is a can of molded pulp with a straight tubular or cylindrical wall, the opposite sides of which are entirely parallel. Obviously such a can may, on the present apparatus, be made as deep or shallow as required. Since a slight divergence is required between the inner periphery of the die 566 and the work so that the die will be parallel with the work when pushed laterally as shown in Figs. 6 and 9, the inner periphery of the die -is slightly frusto conical but the angle is necessarily somewhat exaggerated in Fig. 9 in order to illustrate this point.

The pendular movement of the spindles 49 is so slight that it does not materially interfere with the mesh of the gears at their upper ends whereby all spindles are driven at the same speed.

The dies The mandrels l9 may be so mounted as to idle upon their tubular supporting shafts 21, but preferably the mandrels are also driven at a peripheral speed very closely approximating that of the dies. The driving connections are as follows:

Carried by the vertically reciprocable slide 45 are the bracket arms 66 which support a table 61 upon which we mount the motor 68, the speed reducer 69 on the gearing which drives shafts I0 and II. Shaft 16 moves with the slide and table and carries a pinion at 12 meshing with one of the gears 65 for the rotation of all of the the belt as shown in Figs. 1, 3 and 13. Gears =,=mounted on all the mandrels as shown at I8 rtransmit motion from one to another so that all 'are driven from belt I6 by disk TI in unison with spindles 49 concurrently. Shaft II is mounted of the slide. The shaft II operates a pulley l4 which co-operates with pulley I5 to supporta belt I6.- In each indexed position of the rotary mandrel carriage I8 a disk TI mounted on the corner mandrel is presented to the belt in friction contact therewith to receive motion from the dies 50 (or 500).

I In this-particular apparatus the vertical reciproc'ation of the slide is effected hydraulically. There is a hydraulic cylinder at I9 and the piston rod 80 .is connected with the slide. The synchronous movement of the slide is subject to the control of a valve, of which 8| is the casing and 1 82 is the valve rod. The valve rod is operated by shaft 81.

of spring 96 and carries cam follower 91 subject to the action of cam 98 on said shaft.

The earns 60 and BI which shift the dies laterally with respect to the mandrels and the work,

derive their motion from shaft 81 through chain I00, shaft IOI, bevel gearing I02, cross shaft I03, chain I04, and cross shaft I05.

The cam 36 which operates the elevator 35 receives its motion from the drive shaft 81 through chain I01.

The rotatable mandrel carriage receives its indexing movement and the conveyor chains I receive their intermittent advance from a duplex Geneva motion. The rotary mandrel carriage I8 is mounted on a tubular shaft I08 through which extends an inner shaft I09. The Geneva gears II 0 and III are mounted on shafts I08 and I09 respectively, and are spaced apart to receive the single Geneva pinion disk II2 which has a tooth peg I I3 projecting from one of its faces and a like peg I I4 projecting from the other of its faces at a diametrically opposite point on the disk. Despite the fact that the Geneva motion isduplex, using a single pinion disk, its operation is conventional. The peg II3 operates the Geneva gear I in alternation with the operation of Geneva gear IIO by peg II4. Thus, each of the shafts I09 and H0 are alternately advanced ninety degrees. Shaft IIO delivers its motion directly to the mandrel carriage I8 mounted thereon, while shaft I09 is connected by a chain I I5 with the drive sprocket which actuates the conveyor I5.

The operation of the machine will now be briefly reviewed:

. The conveyor I5 carries trays H in the direction indicated by the arrow in Fig. 1. When these trays are placed upon a conveyor they contain wet pulp blanks I6. In the step by step advance of the conveyor these blanks are positioned beneath the lowermost mandrels I9 on the indexing mandrel carriage I8. The elevator 35 moves upwardly to dislodge the blanks from The lever 92 is subject to the tension the trays and to thrust them upon the mandrels. The mandrels are simultaneously subjected to vacuum which holds the cups in place thereon, the dwell of the elevatorbeing sufficient to assure opportunity of the vacuum to act on the blanks.

During this operation the blanks carried by the mandrels whichare uppermost on the indexing carriage I8 are being worked upon by the dies 50. These dies have descended over the blanks and at the same time have been pushed laterally out of registry with the mandrels as shown in Fig. 5 by the mechanism illustrated in Fig. 4. The dies and mandrels are preferably but not necessarily heated, and they areso nearly the same diameter that the lateral pressure of the die uponthe work is not localized, but is distributed over the surface of the work. As the die moves downwardly and during its. operation in its position of full engagementwith the work,

angle of side which deviates slightly from the side of the mandrel so that in the inclined position of the die its surface which contacts the work will be parallel to the underlying portions of the mandrel as shown in Fig. 6.

Before the die ascends to free the work for rotation with the indexing carriage I8, the lateral pressure upon the die is relieved and the die swings into concentricity with the mandrel as shown in Fig. '7, so that it may be drawn straight off the work without contact therewith, as shown in Fig. 8.

The mandrel carriage I8 is now indexed to move the completed articles 40 out of registry with the dies and to bring a fresh set of blanks into registry with the dies. In the course of the indexing movement one set of completed articles is exposed downwardly, and the mandrels carrymandrels empty. It is at this point that the conveyor chain I5 has its intermittent advance to bring a fresh tray of blanks beneath the empty mandrels for the repetition of the sequence of operations above described.

We claim:

1. In a device of the character described for compressing pulp articles, the combination with a cup-shaped die and mandrel receivable therein and slightly smaller in size and rotatably mounted, the angle of the side of the die deviating slightly from the side of the mandrel, of means rotatably supporting the die, said means being pivoted at a point above the mandrel for the lateral swinging movement of the die, and means for laterally swinging said die about the pivotal mounting of its supporting means for the engagement of work on the mandrel, such movement being only sufficient to bring into approximate parallelism the surfaces of the die and the mandrel engaged with such work.

2. In a device of the character described for compressing wet pulp articles, the combination with a rotatable die and a rotatable mandrel, and

means for positively rotating at least one thereof, of a pivoted support for said die upon which said die is movable laterally to bring its inner periphery into engagement with work on the mandrel, means for effecting relative axial movement between said die and mandrel, means for effecting relative lateral displacement between said die and mandrel for the pressure engagement of such work, and vacuum means for holding the work to the mandrel.

3. In a device of thecharacter described for compressing wet pulp articles, the combination with a die member having frusto-conical walls and a mandrel member of complementary form and slightly reduced diameter freely receivable into the die member, of means rotatably mounting said members, means for rotating one of said members, means for laterally displacing one of said members for the engagement of work car ried by the other, and means for concurrently efiecting relative axial movement between said members to introduce the mandrel member into the die member.

4. In a device of the character described, the combination with an indexing mandrel carriage and sets of mandrels projecting from different sides thereof, of means for the intermittent indexing movement of said carriage, a conveyor running past a station at one side of the carriage, means for the intermittent advance of the conveyor during the dwell of the carriage, means at another station of said carriage for acting on the work carried by the mandrels thereof, and means for automatically delivering the work from the conveyor to the mandrels and subsequently receiving work from the mandrels to the conveyor.

5, In a device of the character described, the combination with a rotatably indexing mandrel carriage having mandrels projecting from its various sides, and means for intermittently indexing said carriage to advance its mandrels from a loading and unloading station to a working station, of conveyor means extending past the loading station, a series of trays movable upon said conveyor means and having work receiving portions registering in said loading and unloading station with the mandrels of said carriage, means for advancing said trays intermittently during the dwell of said carriage, and transfer means for positively delivering the work from the trays to the mandrels during the dwell of said trays and immediately prior to the advance of said carriage, and for receiving the work and delivering it to the empty tray from another set of mandrels following the advance of said carriage.

6. In a device of the character described, the combination with a rotatable mandrel carriage having sides and mandrels projecting in' sets from its several sides, of means for the intermittent indexing advance and dwell of said carriage to move said sets of mandrels from a loading and unloading station to a working station and back, die means at the working station and mechanism for actuating said die means to act on work carried by the sets of mandrels at such station, a conveyor means movable past said unloading station and including work receiving pockets, means for the actuation and dwell of said conveyor means in alternation with the actuation and dwell of said carriage, said carriage and conveyor means having overlapping dwell periods, elevator means provided with synchronous operating connections for moving it to and from said carriage during said overlapping dwell periods, said elevator means being adapted to deliver blanks from said pockets to the mandrels of said carriage prior to the indexing of said carriage and to receive work from the mandrels of said carriage subsequent to the indexing thereof, said work being delivered by said elevator means from and to the pockets of said conveyor means.

7. In a device of the character described for the compression of wet pulp articles, the combination with a mandrel carriage having a hollow interior, of tubular mandrel supports projecting from the carriage, mandrels rotatably mounted on said supports and having hollow interiors communicating with interior of the carriage, and ducts extending through said mandrels to the outer periphery thereof, and means for causing the interior of said carriage to vary from atmospheric pressure.

8. In a device of the character described, the combination with a conveyor including tray means provided with pockets, of actuating means for effecting the step by step advance and intervening dwell of the conveyor with respect to a loading and unloading station,'a mandrel carrier mounted to rotate on an axis transverse with respect to 'said conveyor and having mandrels presented toward said pockets in registry therewith at said station, means for eiiecting the step by step indexing movement and dwell of saidmandrel carrier to present successive series of mandrels to successive pockets of said conveyor, an elevator at said station provided with means for advancing and retracting it with respect to said mandrel carrier. twice during the dwell of said conveyor, said indexing means being timed to index the mandrel carrier between the successive advances of said elevator, and said elevator being arranged to lift the work in said pockets to the mandrels and to receive from successive mandrels work to be restored to said pockets, and mechanism-operable on the first advance of said elevator to subject said mandrels to vacuum to hold the work thereto, and mechanism operative upon the second advance of the elevator to subject said mandrels to pressure for the discharge of work therefrom.

9. In a device of the character described, the combination with a conveyor including tray means provided with pockets, of actuating means for effecting the step by step advance and intervening dwell of the conveyor with respect to a loading and unloading station, a mandrel carrier mounted to rotate on an axis transverse with respect to said conveyor and having mandrels presented toward said pockets in reg'stry therewith at said station, means for effecting the step by step indexing movement and dwell of said mandrel carrier to present successive series of mandrels to successive pockets of said conveyor, an elevator at said station provided with means for advancing and retracting it with respect to said mandrel carrier twice during the dwell of said conveyor, said indexing means being timed to index the mandrel carrier between the suc cessive advances of said elevator, and said elevator being arranged to lift the work in said pockets to the mandrels and to receive from successive mandrels work to be restored to said pockets, and mechanism operable on the first advance of said elevator to subject said mandrels to vacuum to hold the work thereto, and mechanism operative upon the second advance of the elevator to subject said mandrels to pressure for the discharge of work therefrom, together with rotatable dies positioned at another station in th indexing of said carriage and provided with means for the rotation of said dies in pressure engagement with the work on said mandrels at said last mentioned station.

10. In a device of the character described, the combination with a conveyor including tray means provided with pockets, of actuating means for effecting the step by step advance and intervening dwell of the conveyor with respect to a loading and unloading station, a mandrel carrier mounted to rotate on an axis transverse with respect to said conveyor and having mandrels presented toward said pockets in registry therewith at said station, means for effecting the step by step indexing movement and dwell of said mandrel carrier to present successive series of mandrels to successive pockets of said conveyor, an elevator at said station provided with means for advancing and retracting it with respect to said mandrel carrier twice during the dwell of said conveyor, said indexing means being timed to index the mandrel carrier between the successive advances of said elevator, and said elevator being arranged to lift the work in said pockets to the mandrels and to receive from successive mandrels work to be restored to said pockets, and mechanism operable on the first advance of said elevator to subject said mandrels to vacuum to hold the work thereto, and mechanism operative upon the second'advance of the elevator to subject said mandrels to pressure for the discharge of work therefrom, together with rotatable dies positioned at another station in the indexing of I said carriage and provided with means for the rotation of said dies in pressure engagement With the work on said mandrels at said last mentioned station, said mandrels being also rotatable and said vacuum applying means continuing effective during the operation of said dies.

11. In a machine for compressing wet pulp cupshaped articles, the combination with a cupshaped die member having a concave interior compression surface and a coacting mandrel member having a convex exterior compression surface, the mandrel member being freely receivable into the die member, of means for rotating one of said members, means for producing relative axial movement between said members in a direction to introduce the mandrel member into the die member, and means for concurrently moving one of said members laterally with respect to the other, whereby to effect the pressure engagement of work between said convex and concave surfaces.

I 12. In a machine for compressing Wet pulp articles, the combination with a carriage and a cooperating relatively stationary frame, of a set of hollow die members, a set of coacting mandrel members freely receivable therein, one of said sets being mounted on the carriage and the other upon said frame, means for concurrently rotating the members of one of said sets, means for moving one of said sets of members axially toward the other in a direction to introduce the several mandrel members into the several die members, and means for concurrently moving the members of one of said sets laterally with respect to the complementary members of the other set for the pressure engagement of work mounted on the members of one of said sets.

13. In a machine for compressing wet pulp articles, the combination with cup-shaped hollow die members having interior wall portions substantially straight sided in an axial direction and circumferentially concave, of complementary mandrel members having wall portions substantially straight sided in an axial direction and circomferentially convex, the mandrel members being freely receivable into the die members and the respective wall portions deviating slightly from each other in an axial direction, means for tilting some of said member'swith respect to the complementary members sufiiciently to bring their respective side surfaces into pressure engagement with work and to substantial parallelism with the coacting surfaces of the complementary members, and means for concurrently moving some of said members axially with respect to the complementary members, whereby to progressively introduce the mandrel members into the die members in pressure engagement with the work.

14. In a machine for compressing wet pulp articles, the combination with a frame, of an indexing carriage mounted thereon and a second carriage movable to and from the indexing carriage upon the frame, a set of hollow die members carried by one of said carriages, a set of mandrel members carried by the other carriage, means for indexing the first mentioned carriage to bring its members into registry with the members of the other carriage, means for advancing said other carriage to receive the mandrel members into the die members, means for rotating at least the members of one of said sets while the mandrel members are within the die members, together with means for laterally displacing the members of one of said sets with respect to the carriage upon which they are mounted, whereby to effect lateral pressure engagement of work between the members of the respective sets, and driving connections for the synchronous operation of said lateral displacing means and the advance of the second mentioned carriage toward the indexing carriage, whereby said lateral displacing means will be effective during such advance.

15. In a'device of the character described, the combination with a die and a mandrel of differ ing diameters, of means for rotatably supporting the die and the mandrel with their axes offset for pressure engagementwith the wall of a hollow pulp article mounted on one thereof, and means for the power actuation of both said die and said mandrel at differing rates such that their rela-. tive peripheral speeds in engagement with such wall will be substantially identical.

16. In 'a device of the character described, the combination with a die and a mandrel, of means supporting said die and mandrel for rotation upon offset axes for the pressure engagement of the wall of a hollow pulp article between the inner periphery of the die and the outer periphcry of the mandrel, means for producing relative axial movement between the die and the mandrel, and mechanical motion transmitting connections between said die and mandrel positively controlling their relative rates of rotation, said connection being adapted 'to rotate the die and mandrel at approximately the same peripheral speed of contact with the work. I

17. In a device of the character described, the combination with a die and -a mandrel of differing diameters, of means supporting the die and mandrel for rotation upon ofiset axes, means for moving the supporting means axially, whereby to encircle with the die the work upon the mandrel for pressure engagement of the work between the inner surface of the die and the outer surface of the mandrel at one side of the mandrel, and means for driving the die and mandrel at approximately the same relative peripheral speeds, whereby neither will rotate appreciably respecting the work.

18. In a device of the character described, the combination with a die having an inner pressure surface, of a mandrel having a complementary external pressure surface. said mandrel being almost as large as the die in diameter, whereby the die and mandrel are adapted for cooperation with a rolling action to distribute their pressure upon the intervening work, means mounting the die and mandrel for rotation upon offset axes whereby to roll the work between said surfaces, and means for rotating both the die and the mandrel, said means including synchronized driving connectionsfor operating the mandrel and the die at approximately the same relative peripheral speed, whereby neither of said surfaces will appreciably rub the work.

19. In a pulp pressing machine, the combination of a cup-shaped die and a mandrel slightly smaller in size and freely receivable therein, of means ro-tatably mounting the die and the mandrel, means for rotating the die, a source of power, and actuating means connecting said source and said die for axially moving the die with respect to the mandrel, and for displacing the die laterally with respect to the mandrel prior to the completion of its axial movement whereby to press mandrel-supported work in the course of such rotation and axial movement.

ERNEST HUFF. ANDREW KEIDING. 

